Relationship of oncogenes (sFas, bcl-2) and cytokines (IL-10, alfa-TNF) with the activity of systemic lupus erythematosus

Background: Different oncogenes (Fas and bcl-2) and diverse cytokines (IL-1 0 and alfa-TNF) may have an effect on the regulation of apoptosis. The majo rity of studies to elate have evaluated only one or two of these elements i ndependently and it is difficult to obtain a global view of apoptosis disre gulation in the pathogenesis of systemic lupus erythematosus (SLE) and thei r role in disease activity. The aim of this study was to evaluate serum lev els of sFas, bcl-2, IL-10 and alfa-TNF in human SLE patients and to analyze their relationship with disease activity and with regulation of the apopto tic process. Patients and Methods: Serum levels of sFas and cytokines IL-10 and alfa-TNF were studied by enzyme-linked immunoabsorbent assay. Bcl-2 an tigen expression was analyzed in lysated lymphocytes from 51 SLE patients. The disease activity was analyzed according to the SLE disease activity ind ex (SLEDAI). Results: SLE patients had higher levels of sFas (p = 0.0006) a nd alfa-TNF (p < 0.0001) than the control group. No relationship was found between the levels of bcl-2 and IL-10 from SLE patients and the control gro up. However, there was a significant correlation between SLEDAI and bcl-2 ( p < 0.001) and IL-10 levels (p = 0.004). In contrast, we found that sFas an d alfa-TNF were not related with disease activity. A significant correlatio n of sFas with alfa-TNF serum levels (p = 0.003, R = +0.41) and bcl-2 antig en expression (p = 0.02, R = +0.32) was observed. Conclusion: sFas and alfa -TNF serum levels are increased in SLE patients. sFas levels seems to be se condary to alfa-TNF action, which is enhanced in inflammatory conditions su ch as SLE. Bcl-2 antigen expression and IL-10 serum levels are related to t he maintenance of SLE activity. These alterations may interfere with the ap optotic process, promoting lymphocyte hyperactivity secondary to increased cytokine levels, and causing the characteristic features of SLE.